1. Field of The Invention
This invention relates to gas cooling apparatus and, more particularly, to evaporative air cooling apparatus using direct and/or indirect cooling methods for multiple cooling purposes.
2. Description Of The Prior Art
U.S. Pat. No. 2,083,436 (De Bothezat) discloses an evaporative air cooler used to cool another air flow. The apparatus uses a radiator with tubes through which air flows, and the walls of which receive water for cooling the flow of air through the tubes.
U.S. Pat. No. 2,162,158 (Coey) discloses several embodiments for cooling air. Included in the embodiments is a heat exchanger in which fresh air is drawn in and is cooled by water flowing through a coil. Air from the cooled chamber is then directed toward a cooling system in which water is evaporated. Air flowing through the evaporative system is cooled and is then supplied to the input side of the cooling heat exchanger.
U.S. Pat. No. 2,214,880 (Crawford) discloses another system in which cooling and dehumidifying in air flows take place. An evaporative cooling system is used to help cool water flowing through cooling coils, and the cold water is then in turn used to cool water in a cooling tower.
U.S. Pat. No. 3,350,892 (Kelley) discloses a two-stage air cooling system in which air is supplied to a chamber which has its own system for cooling air. Water from nozzles is cooled as air passing through a chamber evaporates the water to cool the air. The water is condensed and its temperature is lowered, and the chilled water then passes through a heat exchanger for cooling incoming air. The cooled air then passes through a coil, and the coil is cooled by water and spray chamber which further cools the air flowing through the coil.
U.S. Pat. No. 4,380,910 (Hood et al) discloses a multi-stage cooling system in which one stream of air is passed through a water saturated evaporative cooling medium where the water is cooled as well as the air that passes through it. The cooled air passes through a heat exchanger and out of the system. There is a second air stream in the air passing through the heat exchanger and that air is cooled by the first air stream. The second air stream then passes through a water cooled exchange element that is cooled by water from a saturated cooling pad. The second air continues through cooling coils for further cooling. Several stages of direct and indirect cooling are employed, and recirculating water is used in each of the stages.
U.S. Pat. No. 4,429,735 (Nomaguchi et al) discloses a air cooling system in which air flows from a room through a vent and water droplets from a tank are picked up in the air flow. The water evaporates in a heat exchanger and cools outside air that passes through the heat exchanger.
U.S. Pat. No. 4,926,656 (Hickley et al) discloses a cooling system in which air is moved by a fan through a coil and chilled water flows through the coil. The water is chilled when the air passes through a wet evaporative medium, and the air is further cooled in the evaporative medium also. The cooled air then passes from the apparatus to the structure through a delivery conduit.
It will be noted that all of the above discussed patents utilize some type of multiple air flow and direct and indirect cooling of the multiple air flows. In virtually all cases, the apparatus are relatively complicated, cumbersome and typically require multiple fans and multiple pumps, nozzles, and the like. The apparatus of the present invention utilizes indirect as well as direct cooling and multiple air flows, but only a single fan or blower is required. Heat exchanger elements are used in conjunction with evaporative media, and there are two types of air flows, one air flow through a dry channel and one air flow through a wet channel. In one embodiment, a second fan is used for a cooling tower. Although the cooled fluid will be referred to as "air" throughout, it is intended that the term include various two-atom gases as the invention is applicable to these fluids as well.